Process of combustion



Aug 16, 1927. 1,639,202

B. VALJEAN PROCESS OF COMBUSTION Filed Sept. 5, 1922 2 Sheets-Sheet 2 ,W Z Q4511 IZQGIJi/W \Ben Val ecug,

1M I 7:1 5 fiifirne A Patented Aug. 16, 1927.

UNITED STATES PATENT OFFICE.

BEN VAIJEAN, OI SAN DIE GO, CALIFORNIA, ASSIGNOR TO VALJEAN CARBURETOB COMPANY, OF SAN DIEGO, CALIFORNIA, A CORPORATION OF CALIFORNIA.

PROCESS OF COMBUSTION.

Application filed September 6, 1932. Serial No. 588,185.

This invention relates to process of combustion and, in its particular aspect, to improvements in the process ofcombustion for whichv I received Letters Patent #1,280,596, dated October 1st, 1918.

There are several objects of the present invention among which I may note preliminarily the following:

1-definite location of the tion of combustion, and

2-increase in amount of combustion in point of incep any apparatus of given size.

In order to make the present invention fully clear and to show fully how it accomplishes these and other objects (which will hereinafter appear) it will be best for me first to ive axbrief statement of the eneral underlying process on which said etters Patent is based. With a preliminary understanding of that process the improvements of the present invention may be most readlly understood. o

I have described in said Letters Patent one process of combustionwhich involves fundamentally the formation of a nonexplosive thin mixture of air and gaseous fuel and the combustion of that thin mixture by the addition of a body comparatively rich in fuel-by the addition of either a proper amount of pure fuel or of a proper amount of a rich mixture of fuel and air. The result of such an operation is that the combustion takes place, so to speak, out of the lean mixture rather than out of the rich mixture, as had theretofore been the case;

and high efficiency of combustion results from this particular operation. It will be unnecessary to go into further details explaining why I attain higher efficiency of combustion. I h

One of the means explained in said Letters Patent by which I attain the objects of that invention isthe introduction of a jet of air into a maintained atmosphere of gaseous fuel, under such circumstances (proportion of the apparatus parts, etc.) that the jet of air draws with it the gaseous fuel and forms a stream of relatively thin mixture which may be finally mixed with a comparatively small volume of either a part of the gaseous fuel atmosphereitself or with the concurrently formed stream of relatively rich mixture, or with both. Combustion of course, takes place at a point where that admixture occurs; but in the process explained in said Letters Patent these admix tures were, as I might say, merely allowed to occur, and were not positively or forcibly caused to occur. It is this positive or forci- 'ble causation of admixture and preci itation of combustion that is one of the su ject matters of the present invention. It will be 4 understood that the mixtures or bodies (the 'relates to the use'of a multiplicity 0 air jets introduced and maintained in a gaseous fuel atmosphere, in such a manner that each air jet carries on the herein described process independently of and without interference by any other air jets. 'By this provision, and the provision ofan air entrance gap or other means for forcibly mixing the lean and rich mixtures, together formed by these jets all as hereinafter described, I am enabled greatly to increase the amount of combustion capable of being producedin an apparatus of given size and also to increase the flexibility of the process as carried on in any given piece of apparatus, particularly in regard to the amount of combustion. That is, any given piece of apparatus may be used for a larger range of heat production and. still keep up the high efliciency of the process. And in connection with this flexibility of operation the provision of means for definitely controlling the oint of combustion inception is of great importance as by that means the flame and zone of heat production may be virtually restricted to one location, substantially regardless of the amount of fuel consumed and the amount of heat produced. This definite location of combustion has many advantages which will hereinafter appear, but it may be briefly stated here as providing for the more accurate and eflicient application of heat in any given piece of apparatus and as providing that only certain parts of the apparatus need be made of a specially heat resisting conpurpose I refer to struction whereas all other parts may be made of lighter construction and still be enduring.

In order now to give a clear understanding of the present invention, 1 shall proceed to give a detailed description of certain specific forms of apparatus and of the specific forms of process carried on in those apparatus, it being understood that the process is not limited necessarily to the particular forms herein described; and for this the accompanying drawings in which Fig. 1 is a vertical central section of one form of apparatus; Fig. 2 is a plan section on line 2--2 of Fig. 1; Fig. 3 is a vertical central section of another form of apparatus; Fig. 4 is avertical central section of another form of apparatus; and Fig. 5 is a diagrammatic showing of another form of apparatus.

In Figs. 1 and 2 I illustrate in simple form a typical furnace structure in which is the firebox (the chamber in which the coinbustion takes place) and 11 represents a chamber below the firebox. This chamber 11 below the firebox may be nothing more than merely a support for the other parts of the furnace; or it may be used as a means to feed air under pressure to my combustion apparatus as will be hereinafter described. The part of the apparatus that I term the carbureter 12 is located in chamber 11 and, in this particular piece of apparatus, is supported in proper relation to combustion chamber 10 by a means which will be described. Carbureter 12 is formed of any suitable material; it may be made of light sheet metal in case it is not desired to use pressure on the air or heavy oils and it is not therefore necessary to develop a large amount of generating heat to vaporize the required quantity of oil. It is here shown as being substantially cylindrical in form, with a flat bottom 13 and-cylindrical side wall 14:, the side wall being provided with perforations 15 preferably spaced not only around the carbureter wall but also vertically thereof. The number of perforations, their individual sizes, and spacings, and the number of rows in which they are placed, are matters determined as hereinafter stated. It will be apparent however, that it is not necessary to have a. number of rows of perforations; that the carbureter shell may be comparatively shallow and only one row of perforations used.

Tlhe carburcter has at its top an outlet ripening it? whichv registers with opening 17 in bottom of combustion chamber 10; but as will be seen from the drawings the openings 16 and. 17 are spaced from each other by an air entry gap 1.9 preferably extending completely around the edges of the openings as illustrated, and of uniform width.

The details of apparatus and construction whereby this uniform width is easily attrained are explained in a co-pending application oncombustion apparatus, filed on even date herewith, Serial N 0. 586,194, which issued into Patent- No. 1,512,869 dated October 21, 1924. It is sufficient for the present description to say that carbureter opening 16 is formed by two annular rings 20 and 21, above and below the upper sheet metal wall 22 of the carbureter shell. Ring 20 has an annular bead 23 around opening 16; and the bottom wall 18 of chamber 10 has a corresponding annular bead 24 at its lower face around its opening 17; so that air gap 19 is restrictedly formed between these two rims, and, the space outside gap 19 being comparatively unrestricted, the air has free access to the gap. This arrangement promotes uniformity of operation around the whole length of the gap. This gap is determined in its width by the hanging of the carbureter on tracks 25 which roject from the under side of bottom 18, anges 26 on ring 20 overhanging the tracks 25.

Fuel for creating the gaseous fuel atmosphere in the carbureter may be introduced in any suitable manner. If originally gaseous fuel is used it may be introduced into the carbureter in any suitable manner, as will be readily understood; the only requisite being that the carburetor shall be maintained full with a gaseous fuel atmosphere. If originally liquid fuel is used it may be introduced through a fuel pipe 30 through which the liquid fuel may drop through openings 16 and 17 onto the bottom of the carbureter as illustrated. Here the liquid fuel, s reading out thin, is gasified or vaporized y reflex heat from the flame and the gases and vapors then fill the car ureter. Any feed means will sufiice that gets the fuel onto the carbureter bottom or causes it to be vaporized and delivered into the carbureter.

The air entering the device through openings 15 and gap 19 may be merely under atmospheric pressure, in which case it may be admitted from the atmosphere through an opening in door 31 of chamber 11, or by merely leaving the door slightly open. On the other hand if it is desired to operate under an air pressure then chamber 11 may be closed and supplied with air under pressure; and I may also divide chamber 11 into two compartments by a flange or partition 32 (which may conveniently be a flange attached to carbureter shell 12) and then air may be admitted to the upper compartment for gap 19 through a valve controlled pipe 35 and air may be admitted for perforations 15 to the lower compartment through a valve controlled pipe 36. These air introductions may be under any suitable pressure, either alike or different; and suitably controlled.

In Fig. 3 I show another and simpler form of apparatus and one in which the process procedure is rhaps more simple than in the form of Figs. 1 and 2. Consequently, although the form of Figs. 1 and 2 and the process procedure therein is in some ways preferable, I shall explain first the simpler form of process carried on in the apparatus of Fig. 3. In this apparatus the carburet-er 12 has a single air opening 1.; in its bottom. The liquid fuel is introduced through pipe 30 to the annular pan surrounding the upper part of carbureter 12. The liquid fuel standing in'the bottom of this an receives reflex heat from the flame, causmg its vaporization and causing carbureter 12 to be filled at all times with vapor. An air inlet at 41 may be opened to admit air over the fuel in pan 40 for the purpose of initial neration. The combustion chamber is i'l ustrated at 10; and at the entrance to that chamber there is a combustion precipitating baffle plate 19.

It will be unnecessary to explain the method of generating combustion beyond saying that the liquid fuel first introduced to pan 40 is simply ignited; and its burning produces enough heat to vaporize more fue than is burned by the air coming inthrough 41; with the result that this vapor i'ssupplied with air for combustion through opening 15 Then as soon as the combustion that is supplied with air through 15 becomes intense enough to vaporize the .oil without continuation of the flame in pan 40, the cover at ll is ut on, extinguishing the flame in pan {10. hen combustion goes on in the manner now to be described. A jet of air as indicated at A projects itself rapidly up into the atmosphere of vapor in carbureter shell 12. This jet of air of course tends to draw upwardly along with it the immediately surrounding parts of the gaseous atmosphere; and in so doing, as will be readily understood, it creates a less rapidly upwardly moving stream L of lean mixture and then an immediately surrounding more slowly moving film E of explosive mixture, and then a surrounding comparatively very sluggish stream R of rich mixture; and then of course outside the rich mixture stream there is the immediately surrounding atmosphere of pure gaseous fuel. Of course, it will be understood that these streams merge by insensible graduations one into the other, but that does not aflect the fundamental facts here presented. lVith the apparatus properly proportioned (the drawings show the apparatus in proportional scale, and I. ive hereinafter some typical dimensions) the stream of lean mixture here has an average composition very near to explosibility. As I have pointed out in my prior patent the composition of the lean mixture may be very close to explosibility and.

yet be non-explosive. The amount and com of proportions as nearly to theoretically perfect eombustibility as may be. The volume of the lean mixture may be much greater than the volume of the rich mixture stream, due to the fact that the lean mixture in its average composition is much nearer explosible proportions than the rich mixture, and therefore it is only necessary to add a comparatively small quantity of the rich mixture to the lean mixture to make a perfectly combustible admixture. Furthermore, the rich mixture stream may be in average composition much richer than is absolutel necessary to prevent its combustion; an this may be due at least partially to the fact that the upwardly moving stream of rich mixture may carry up with it and around it an envelope of practically pure gaseous fuel. The explosive film E may have been kept from combustion by being cooled by the two immediately contacting cool mixturestreams, or by the interference of non-combustible gases. It should also be remembered that when pressure is not applied to the air that the slow flow and the large volume of the explosive mixture indicate that its formation is too slow to support continued combustion in the space it- All of this com osite upwardly moving stream strikes ba e plate 19*; and upon strikin that plate the streams are immediately orced out laterally along the under side of the plate to its periphery; and by such action the several streams are forced one through another and perfect admixture is thereby occasioned. The streams being thus admixed, combustion is precipitated at that point-around the edge of plate 19. It will be seen that this combustion precipitation is caused by the positive and forcible admixture of the several mixture streams with each other and also, in some cases at least, with a stream of more or less pure gaseous fuel; or with the immediately surrounding or adjacent parts of the gaseous fuel atmosphere and that this positive and forcible mixture is caused by directing one or more of the streams laterally-transverselyrelatively to the previous direction of stream movement.

It is one of the peculiar features of the process as here carried out that the combustion is. under practically all conditions, 10- calized to begin at the point of positive admixture. Of course, if the fuel supply be cut down to the point Where only a small flame will be maintained, the mixture streams may intermingle before reaching plate 19 and combustion under those conditions will take place in the carbureter. But when combustion is taking place in the normal minimum quantity for which the apparatus is designed, it will always be precipitated at plate 19. Then if more fuel is admitted to increase the quantity of combustion the inception of combustion: always takes place at plate 19 as that is where admixture occurs under all conditions. The size of the flame and amount of combustion may vary up to the maximum of which the apparatus is capable but combustion always starts at that point. If the plate or some equivalent means were not present it can readily be seen that when a large quantity of vapor is being drawn upwardly in the mixture streams and the air is not dashed while yet lean into the vapor combustion might. be smothered out until farther up where a further supply of air would be received.

Now in the apparatus shown in Figs. 1 and 2 each opening 15 performs substantially the same function as is performed by the single opening 15? in Fig. 3. At each opening (as diagrammed illustratively for one of the openings in Fig. 1) there is a et of air A, a relatively rapidly moylng stream of lean mixture L, a surrounding slowly moving stream of explosive mixture E and an outer surrounding sluggish stream of rich mixture R. The holes 15 are far enough apart that the outermost part of the composite stream from any one openmg 15 does not interfere with the outer part of the composite stream from any other opening, the gaseous fuel atmosphere between the composite streams remaining substantially undisturbed. Thus, as will be readily reco nized, the spacing between holes 15 depen s somewhat upon the sizes of the individual holes. It depends also upon the velocity at which air is to be taken through those-holes. In the drawings I have shown a proportionate size of parts and hereafter g1ve typical dimensions, these proportions and dimensions being for operation of the device when taking in air directly under atmospheric The proportion of air introduced at gap 19 may vary within fairly wide limits in proportion to the amount of air taken 1n through openings 15. The primary function of the air introduced through gap 19 is to cause thorough and practically instantaneous admixture of the streams of mixture or of the streams of lean mixture and the streams of substantially pure gaseous fuel; but of course the air introduced at 19 may also enter into the combustion as an active combustion factor, either producing a lean flame (a blue or non-luminous flame) under certain conditions or producing a fat flame (a luminous flame) under certain conditions. Under certain conditions, and particularly when the fuel feed is increased to the maximum, there may be a certain amount of fairly pure gaseous fuel carried up with the mixture streams, over and above the amount necessary for forming a perfectly combustible mixture with those streams; and the air entering at 19 may supply the necessary oxygen for the combustion of that excess fuel.

Under low burning conditions this excess may be small or non-existent; whereas under high burning conditions the excess may even approach the maximum that air through 19 is capable of oxygenating. The introduction of air at gap 19 has also the function of preventing eddy currents entering the carbureter from above and from thus disturbing the gaseous fuel atmosphere.

In the form of apparatus shown in Figs. 1 and 2 typical proportionate dimensions for operation under atmospheric pressure may be as follows. The carbureter may be 28 inches in diameter and 10 inches deep over all and its wall perforated with holes, 15, in two rows, 20 evenly distributed holes to the row, and the spacing between the rows being approximately 3 inches. The holes of the lowermost row may be not more than 1 inches above the bottom of the carbureter and they ma be inch in diameter and the holes of t e upper row may be inch in diameter (the holes may be of uniform size but .if anything I prefer to make the lower holes a little largerthan the upper holes). The openings at 16 and 17 are 12 inches in diameter and the gap at 19, 4 inch wide. A burner of this size and type will operate successfully consuming as little as A; gallon of fuel distillate an hour or as much as 8 gallons per hour by natural draft. By enlarging 16 and 17 to 24 inches and gap 19 to inch twice that amount of oil can be burned with proper draft-and. by enlarging holes 15 and applying pressure 100 gallons of oil per hour may be burned. At its lowest practical burning capacity the flame has a tendency to be blue while at its highest practical burning capacity the flame tends to be luminous. Consequently, if we decrease the size or number of openings 15 and also correspondingly decrease course, by increasing them beyond the proper limiting proportions I would then obtain nothing but an ordinary smoky flame.

In the form shown in Fig. 3 proportionaldimensions maybe: carbureter 12 may be r. 7 inches in diameter and 6 inches deep and hole-15* its opening around a bottom and i ably contro to the car extin teen sixt -fourths.

inches.

' 'ets from spreading so -fere with the to 2 inches in diameter. Combustion chamber 10' inches in diameter and baffle plate 19 may be 4 inches in diameter. Ap aratus of such size will operate successfully in the manner heremay also say in this connection, that .bafile plate'19" may of course be constructed in any suitable manner and of any suitable ma terial and be supported in any suitable way.

Fig. 4 shows in proper proportions an apparatus designed particularly to operate under air pressure and also modifications that may be applied to the other forms of apparatus. Here carbureter 12 has a dished bottom 13" and three rows of holes 15". Pipe 30 controlled b valve 30 supplies liquid fuel to the car ureter 36 supplies air under suite pressure to casing 11". An auxiliary air inlet is provided at the annular openin 19". To operate, oil is admitted v ureter bowl and ignited and air pressure turned on adually so as not to ish the flame efore it is fully started. oles '15" of the bottom row are tilted downward to direct their air jets down onto the fuel surface to aid in generation. The correct proportions are shown in the drawings.

There may be twenty holes to each the holes of the bottom row being twenty one sixty-fourths inch, middle row nineteen sixty-fourths, and upper row fif- The carbureter bowl is eight inc es .in diameter, the air pipe three row,

- This apparatus is o 'eratableonly under air pressure. The ho es 15" large and close spaced. This does not mterproper operation of the process as it would under natural draft, because the increased speed of the air jets prevents the much and also forcithe atmosphere of combustible the spaces between them and pens it u as it were, due to the high pressure of the ets; thus kee ing up the atmosphere of fuel vapor aroun each jet. The carbureter to is wide open to pass the increased vo ume of air gases and vapors and because when pressure is used there is no danger of eddy currents entering the chamber from above. I

As illustrated, both the baflle plate and the airgap may be dispensed with; and here the combustion precipitating admixture is occasioned by the orced jets from the holes 1y draws vapor into (or at least the size of plate 19) may be 6- shows some are relatively 'izes the draft on all parts streams reach the central upper part of the 'carbureter.

It will be easil understood how aseous,

instead of initial y liquid fuel may e supof these carbureters to carry on plied to any without the necessity of enterthe rocess ing into details, it can readily be seen that the various apparatus may be reversed, so to speak, so that the air jets are projected outwardly into the gaseous :Euel atmosphere. See Fig. 5 where I illustrate diagrammatically such an apparatus. Here the air jets are projected outwardly through openmgs 15 m a central air drum 50, and annular air entry gaps to precipitate combustion may be located at 19 or 19 or both.

I have now described several different specific forms of apparatus in which the process may be carried out; but it will be understood that these forms of a paratus do not by any means indicate all tli e difierent the forms here illustrated being'only of those which have been developed for commercial application of the process.

The rocess as here described requires the maintainance of a comparatively stagnant atmosphere of gaseous fuel; what I mean by a comparativelystagnant atmosphere is one that is uniformly maintained and m which a uniform atmosphere of gaseous fuel is maintained around each jet. The parts of the gaseous atmosphere around the jet or jets may, as a matter of fact, be in actual motion; and where pressure .is used, the mo-.

tion of this gaseous atmosphere" around these jets may be quite rapid. It will be understood how the action of the air jet draws the gaseous atmosphere into the spaces between them. In apparatus operating under atmospheric pressure only, this movement of gaseous atmosphere into the spaces between the jets is comparatively slow, and it is necessary to maintain a comparatively wide spacing between jets in order to 'kee the gaseous atmosphere there and in or er to prevent adjacent jets from interfering with each-other. But where the air jets are fed under pressure, it is not necessary to have such wide spacing of jets, as the movement of the gaseous atmosphere into the spaces between the jets is more rapid.

The symmetrical arrangement .of the air entry equalizes the fire and therefore equalof the carbureter and prevents the formation of any eddy currents which would have a tendency to cause air or gases or vapors to be drawn downwardly into one side of the carbureter. The air gap, as I have noted, also prevents air currents entering the carbureter from above, and forms an effective cover for the carbureter to prevent such eddy currents from entering it.

Generally, it will be noted that air is admitted in such a way as not to remove the atmosphere of gaseous fuel or to disturb its uniform distribution; and that all other conditions, such as eddy currents, are prevented that will disturb the uniform condition of the gaseous atmosphere. The result of this procedure is that the streams of air passing through the combustible vapor are delivered rapidly in large quantities for combustion, in admixture with the vapor as a lean mixture. The idea is not to mix the air with the vapor rapidly or to contact the air with the vapor quickly but to mix the air and vapor slowly and burn the mixture, while it is lean, in an atmosphere of vapor. In this manner of carrying out the process the air must be in motion or under more than atmospheric pressure and the combustible vapor or gas must be comparatively stagnant and the combustion is sufficiently confined to the lean mixture to render the flame blue or luminous, as desired.

Where pressure is used on the air, no structure such as a partial cover or the use of the air gap 19 is needed to prevent air currents from entering the carbureter drum. Indeed no drum is absolutely necessary at all for the urpose of confining the body of gaseous iiiel, because the inwardly directed air jets, under pressure, will keep the vaporous atmosphere drawn inwardly and thus keep it properly located in the space into which the air jets are projected. The action of the air jets, at high velocity under ressure, keeping the spaces between the jets lled with the gaseous fuel, prevents the surrounding atmosphere from being drawn in between the jets.

Generally speaking, with heavier air pressures, the air entry holes may be spaced more closely together, within reasonable limits. This is also helpful for developing the reflex heat from a more intense combustion to vaporize heavier oils. It is also advantageous to tip the lower jets, nearest the fuel to be vaporized, downwardly so air is brought more intimately into contact, with the fuel. This not only aids in generation but also in oxidization of fixed carbon deposits from heav oil. The generation and vaporization of t e heavier oils may be further increased by the use of a baffie refleeting the heat of combustion upon the oil to be consumed; or such heavier oils may be either preheated or prevzrporized in or by the heat of combustion. before being introduced into the carbureter.

Having described a preferred form of my invention, I claim:

1. The process of combustion that involves forming a substantially quiescent body of gaseous fuel, directing into such body a plurality of air jets in spaced relation, each jet carrying with it a surrounding part of said gaseous fuel to form a stream, the interior portion of which is too thin for ready combustion and the outer portion too rich for ready combustion, maintaining such streams out of interference with each other, whereby no combustible mixture is formed, there after positively causing a combustible admixture of the thin and rich portions of each jet stream, and burning the admixture.

2. The process of combustion that involves forming a substantially quiescent body of gaseous fuel, directing into such body a plurality of air jets in spaced rela-' tion, each jet carrying with it a surrounding part of said gaseous fuel to form a stream, the interior portion of which is too thin for ready combustion and the outer portion too rich for ready combustion, maintaining such streams out of interference with each other, whereby no combustible mixture is formed, thereafter admitting additional air to positively cause a combustible admixture of the thin and rich portions of each jet stream, and burning the admixture.

3. The process of combustion that involves forming a substantiall quiescent body of gaseous fuel directing into such body a jet of air, said jetcarrying with it a surrounding part of said gaseous fuel to form a stream, the interior portion of which is too thin for ready combustion and the outer portion too rich for ready combustion, thereafter positively causing a combustible admixture of said thin and rich portions of said stream, and burning the admixture.

4. The process of combustion that involves forming a substantially quiescent body of gaseous fuel, directing into such body a jet of air, said jet carrying with it a surrounding part of said gaseous fuel to form a stream, the interior portion of which is too thin for ready combustion and the outer portion too rich for ready combustion, thereafter positively causin a combustible admixture of the thin an rich portions of said jet stream by the addition of air, and burning the admixture, the upper limit at which combustion is insured being defined by the contact of the additional air with said stream.

5. The process of combustion that involves forming a substantially quiescent body of gaseous fuel, directing into such body a jet of air, said jet carrying with it a surrounding part of said gaseous fuel to form a stream, the interior portion of which is too thin for ready combustion and the outer portion too rich for ready combustion, directing additional air across the line of flow of said jet stream to insure a combustible admixture of the thin and rich portions of said stream, and burning the admixture, the point at which the additional air intersects the stream defining the upper iimit at which combustlon is insured.

In Witness that I claim the foregoing I BEN VALJEAND 

